上海市空气中不同粒径颗粒物对儿童急性呼吸系统影响的定群研究

A panel study on the acute respiratory effects of ambient particles of different sizes on children in Shanghai

目的研究不同粒径颗粒物数量浓度短期暴露对儿童呼吸系统的影响。方法采用定群研究设计,于2018年11月至2019年6月,在上海市某小学招募65名6~9岁小学生。随访3次,每次随访时测量受试者的用力肺活量(FVC)、第1秒用力呼气量(FEV_(1))、呼出气一氧化氮(FeNO)的水平并收集颊黏膜样品;同时监测每次随访开始前3 d至随访结束这一时间段校园内的不同粒径颗粒物数量浓度(PNC)及温度和湿度水平。采用线性混合效应模型分析不同粒径PNC与儿童呼吸系统健康指标之间的关联。结果线性混合效应模型分析结果显示,滞后2 d的PNC_(0.25~0.40μm)(粒径为0.25~0.40μm的PNC)每升高1个IQR个/cm^(3),FVC、FEV_(1)及ACE分别下降60.15(95%CI:88.97,31.32)ml、34.26(95%CI:63.22,5.31)ml、6.00(95%CI:9.15,2.84),FeNO升高12.10%(95%CI:3.05%,21.95%)。不同粒径PNC升高相关的指标效应值存在粒径越小,相关的效应越大的趋势。结论颗粒物短期暴露与儿童肺功能、颊黏膜微生物多样性降低及气道炎症反应升高有关;颗粒物粒径越小,其对儿童呼吸系统健康的影响可能就越大。

Objective To explore the association between size-fractionated particle number concentrations(PNC)and respiratory health in children.Methods From November 2018 to June 2019,there were 65 children aged 6-9 years from an elementary school in shanghai recruited in this panel study with three rounds of follow-up.The forced vital capacity(FVC),forced expiratory volume in the first second(FEV_(1)),and exhaled nitric oxide(FeNO)levels were measured and buccal mucosa samples of children were collected at each follow-up visit.The level of PNC,temperature and humidity of the elementary school was monitored from 3 days before each physical examination to the end of the physical examination.The linear mixed effects model was used to analyze the association between PNC and indicators of respiratory health in children.Results Linear mixed effects model analysis revealed that,at lag 2 day,an interquartile range increase in PNC for particles measuring 0.25-0.40μm was associated with the absolute changes in FVC,FEV_(1)and abundance-based coverage estimator(ACE)about-60.15 ml(95%CI:-88.97 ml,-31.32 ml),-34.26 ml(95%CI:-63.22 ml,-5.31 ml),-6.00(95%CI:-9.15,-2.84)and percentage change in FeNO about 12.10%(95%CI:3.05%,21.95%),respectively.These adverse health effects increased with the decrease of particle size.Conclusion The short-term exposure to particulate matter is associated with reduced lung function,buccal microbe diversity and higher airway inflammation level among children.These adverse health effects may increase with the decrease of particle size.